The present invention relates to an electrically heatable floor covering on the basis of a fabric of natural and/or synthetic fibres, more particularly an electrically heatable carpet, in which a wire-shaped electrical heating element is enclosed in the carpet body.
In a well-known electrically heatable wall covering the electrical heating element is formed by a finely coiled resistance wire i.e. a wire of a material having a high specific resistivity. Such a construction could not be used for a floor carpet as the finely coiled resistance wire would be readily damaged and even broken as a result of the loads applied to the carpet, such as footsteps, impressions of (heavy) furniture pieces etcetera.
It is also known to apply an electrically conducting paint in a zig-zag pattern on a carrier of plastics material, such as polyester and to connect such carrier to the proper wall covering, for example wall "paper." Such a heating element in the form of a zig-zag ribbon of electrically conducting paint (so-called carbon paint) could not be applied in a floor carpet either, as the electrically conducting paint would soon break under the influence of the mechanical loads exerted on the carpet in use. For this reason this type of wall covering is used only as electrically heated wall "paper" and as ceiling covering.
From the standpoint of heat distribution heating from the floor covering would be advantageous, as in this manner a temperature gradient -- considered from the floor to the ceiling of the room to be heated -- could be realized which corresponds with the ideal temperature gradient, according to which the room temperature has its maximum value adjacent the floor and decreases towards the ceiling.